GEOLOGY
CRYSTALLOGRAPHY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1
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2
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4
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8
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Detailed explanation-1: -In the primitive cubic unit cell, the atoms are present only at the corners. Every atom at the corner is shared among 8 adjacent unit cells.
Detailed explanation-2: -An atom on an edge is shared by four unit cells, and an atom on a corner is shared by eight unit cells. Thus, only one-quarter of an atom on an edge and one-eighth of an atom on a corner can be assigned to each of the unit cells that share these atoms.
Detailed explanation-3: -The body-centered cubic (bcc) has a coordination number of 8 and contains 2 atoms per unit cell.
Detailed explanation-4: -In a face-centered cubic lattice, a unit cell is shared equally by 6 unit cells.
Detailed explanation-5: -A FCC unit cell contains four atoms: one-eighth of an atom at each of the eight corners (8×18=1 atom from the corners) and one-half of an atom on each of the six faces (6×12=3 atoms from the faces).